1. Field of the Invention
The invention herein pertains to the field of chemical intermediates as the title compounds, useful for the preparation of substituted anilines which are precursor materials for known 2-haloacetanilide herbicides.
2. Description of the Prior Art
Prior art methods for the preparation of substituted nitrobenzenes include the oxidation with peracids of the corresponding optionally-substituted anilines (W. D. Emmons, J.A.C.S 76 3470 (1954) et seq.). Alkylation of sulfones is known, including activated sulfones, such as beta-keto sulfones (Samuelsson et al Acta Chem. Scand. 25, 1555 (1971) and halomethylsulfones (Makosza et al Journal of Org. Chem. 40, 266 (1975). Hydrogenation of nitro-aromatics is well known (see Catalytic Hydrogenation by R. L. Augustine, pp 91, 92, Marcel Dekker, Inc., N.Y. (1965), with a wide variety of anilines therefrom.
U.S. Pat. No. 4,006,183 describes substituted ortho-methylsulfinyl methylanilines by reacting the corresponding substituted ortho-methylthiomethyl anilines with an oxidizing agent, such as H.sub.2 O.sub.2 in the presence of a peracid. In the process of the '183 patent, the oxidation does not convert the amino group to a nitro group or the methylthiomethyl group to a methylsulfonylalkyl group as in the present process. Similar o-methylsulfinylmethyl anilines as in the '183 patent are disclosed in U.S. Pat. No. 3,996,371 and these anilines are similarly prepared by oxidation of the corresponding o-methylthiomethyl aniline, again without formation of nitro groups or o-methylsulfonyl methyl groups as herein. The '371 patent refers to an article by Claus et al, Monatch Chem. 102, 1571-1582 (1971) for the procedures for preparing said o-methylsulfinyl methylanilines.
Substituted anilines prepared from the corresponding o-alkylsulfonylalkyl nitrobenzenes of this invention are useful as intermediates for the production of the corresponding N-substituted-2-haloacetanilide herbicides. Illustrative prior art disclosing the preparation of said 2-haloacetanilides from said anilines includes U.S. Pat. Nos. 4,258,196 and 3,966,811, British Specification No. 2,013,188, Belgian Patent No. 887,997 and Swiss Patent No. 579,348.